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Messages - sd22

Thanks g1. I took a look at the resistors and transistors and R84, 85 and 86 seem to be out of spec. The transistors seem to read alright. I'm going to take a look at that site.
I have a Fender 212r that isnt worth much, but I am trying to repair as a hobby. I am looking to get into projects after taking some previous circuits classes but I'm stumped. The amp works, but through the clean channel I have some background distortion. The distortion channels have separate tone and are fine/unnoticeable. The speakers seem to be fine too. This amp is usually pretty clean but doesn't have that same sound anymore.

I took it apart and found that R84 was on its way out, 470ohm resistor burning and increased in resistance to upper 500ohms. The increased resistance could be forcing more power into other portions causing that breakup but that might be completely wrong. I tried checking some of the transistors and diodes around to see if there was an issue surrounding that, but I didn't find anything conclusive. I'm hoping to get some advise on some places to double check for a source for the excess power flow since a bad resistor likely is due to something else going wrong. I plan to replace the resistor obviously along with any shorted transistors or whatever else I find.

Line diagram linked